Unless otherwise indicated herein, the description provided in this section is not itself prior art to the claims and is not admitted to be prior art by inclusion in this section.
A typical wireless network includes a number of base stations each radiating to provide coverage in which to serve wireless client devices (WCDs) such as cell phones, tablet computers, tracking devices, embedded wireless modules, and other wirelessly equipped devices. In turn, each base station may be coupled with a switch or gateway that provides connectivity with one or more transport networks, such as the public switched telephone network (PSTN) and/or the Internet for instance. With this arrangement, a WCD within coverage of the network may engage in air interface communication with a base station and may thereby communicate via the base station with various remote network entities or with other WCDs served by the base station.
Further, such a network may operate in accordance with a particular radio access protocol, examples of which include, without limitation, Orthogonal Frequency Division Multiple Access (OFDMA (e.g., Long Term Evolution (LTE) and Wireless Interoperability for Microwave Access (WiMAX)), Code Division Multiple Access (CDMA) (e.g., 1×RTT and 1×EV-DO), Global System for Mobile Communications (GSM), IEEE 802.11 (WIFI), BLUETOOTH, and others. Each protocol may define its own procedures for registration of WCDs, initiation of communications, handover between base station coverage areas, and other functions.
In practice, each base station in such a network may be communicatively linked with a signaling controller that carries out various network control functions, such as managing setup of bearer connections between the base station and one or more transport networks, tracking were WCDs are located in the network, paging WCDs, and the like.
By way of example, in an LTE network, each base station (LTE evolved Node-B (eNodeB)) has a communication interface with a signaling controller known as a mobility management entity (MME), and the base station and MME each also have a respective communication interface with a gateway system that provides connectivity with a packet-switched transport network. Typically, the nodes of an LTE network would sit on a wireless service provider's core packet-switched network, and so the base station and each other network entity may have an assigned Internet Protocol (IP) address on that network, and the interfaces between these entities may be defined as logical connections through that network.
In example operation, when a WCD enters into coverage of an LTE base station, the WCD signals to the base station to initiate an attach process. In this process, the base station signals to the MME, the MME authenticates the WCD, obtains and stores a context/profile record for the WCD, and engages in signaling with the base station and the gateway system to set up one or more bearers for the WCD, and the gateway system assigns an IP address to the WCD for use by the WCD to communicate on the packet-switched network. Further, as the WCD moves between tracking areas of the network, the WCD transmits tracking area updates, which pass to the MME to notify the MME where the WCD is located. And when a communication arrives at the network for the WCD while the WCD is in an idle mode, the MME may trigger paging of the WCD in the WCD's registered tracking area to facilitate delivery of the communication to the WCD.
Optimally, a wireless service provider will strategically implement base stations throughout a market area so that served WCDs can move between the base station coverage areas without loss of coverage. Each base station may include an antenna structure and associated equipment, and the wireless service provider may connect the base station by a landline cable (e.g., a T1 line) with the service provider's network infrastructure to enable the base station to communicate with a signaling controller (e.g., MME), gateway system, and the like.
In practice, however, it may be impractical for a wireless service provider to run landline connections to base stations in certain locations. For instance, where a service provider seeks to provide many small coverage areas blanketing a market area or to fill in coverage holes between coverage of other base stations, the service provider may implement many small-cell base stations throughout the market area, but it may be inefficient or undesirable to run landline cables to every one of those small-cell base stations.
To connect a base station with the network infrastructure in such a situation, the wireless service provider may implement a wireless backhaul connection between the base station and another base station of the service provider's network. In this situation, the base station at issue operates as a relay base station, and the other base station operates as a donor base station. In practice, the relay base station includes or is coupled with a WCD, referred to as a relay-WCD, and the donor base station then serves the relay-WCD in much the same way that the donor base station serves other WCDs. Further, the relay base station itself serves WCDs, in much the same way that any base station would.
With this arrangement, when the relay-WCD attaches with the donor base station, the relay-WCD may acquire connectivity and an IP address as discussed above for instance. But based on a profile record for the relay-WCD, the network (e.g., a signaling controller) may recognize that the relay-WCD is a relay-WCD (rather than a normal end-user WCD) and may therefore set up a bearer connection for that relay-WCD with a special gateway system that provides for internal core network connectivity and assigns the relay-WCD with an IP address for use to communicate within the core network. Once the relay-WCD receives that core network IP address assignment, the relay-WCD may then convey that IP address to the relay base station for use by the relay base station as the relay base station's IP address on the core network. The relay base station may then operate as a full-fledged base station of the network, having IP-based interfaces with other core network entities (e.g., a signaling controller, a gateway system, and other base stations), albeit with those interfaces passing via the wireless backhaul connection provided by the relay-WCD, and via the special gateway system.